Archis rosana
This moth is a wide spread pest. It is a polyphage. The moth feeds on plants of more than 130 species and 32 families including fruit and berry crops, trees, some ornamental shrubs, dycotyledonous grasses and some cereals. Its caterpillars cause the maximal damage to the fruit and the berry crops of the families Saxifrage and Rosales.
Biology. Life cycle.
The wing-spread of females is 18–22 mm, of males is 14–19 mm. The fore-wings have an ochraceous-golden or dark-brown color with darker transversal thin wavy strips and several spots. The hind-wings are light-brown with a pinkish-yellow tint on the base. The eggs are elongated-oval, grey-green. The caterpillar is 18–20 mm, from a light-green to dark-olivaceous-green coloration, semitransparent. Its head is nitidous, covered with thin light hairs. The pupa (10–12 mm) is spindle-like, yellow-brown with a more dark back. It settles down in the lumps of leaves or in sigarae, rolled along the main vein of a leaf. An average fertility is 250 eggs. The potential is 430. The size of an oviposition (egg-laying) is 0.7–1.2 cm. The female lays the eggs in one layer in groups (clypeuses) of 40–100 (on an average 60) eggs in the oviposition. It leaves them on the smooth bark of the lower part of boles at a height of 7–27 cm or in the forks of skeletal knags. The surface of the oviposition is covered with transparent waxen substance and the blend of moth scales.
Mode of life
Archis rosana develops during a year in one generation. The moths fly from the end of May till the beginning of August with the maximum of population in the second part of June. Their life span is from 8 to 30 days. The moths are active after sunset. The laying of the eggs starts in 3–5 days after moth emergence. In Ukraine massive laying occurs from the second part of June till the first decade of July. The eggs withstand frost to — 27°C, but they die in the snowless winters. The eggs are mainly laid on shrubs, especially on the currant, where the optimal microclimate conditions are. At first it concerns the absence of wind or faint air streams, the slow cooling of above-ground space in the evening. The emergence of caterpillars begins at a sum of effective temperatures of 40–57°C (higher than 8°C). The massive emergence occurs at a sum of effective temperatures of 700C. The duration of caterpillar development is 25–60 days. Pupation occurs in the places of feeding. In dependence on temperature the stage of pupa takes 8–14 days.
Symptoms of injury
In the beginning the born caterpillars feed together sceletonizing leaves, after they creep onto the tops of shoots. The caterpillars of the 1st-2nd ages gnaw out buds and flower buds. Then they pass to flowers eating stamens, pistils and petals also sceletonizing the young leaves. The caterpillars of elder ages injure ovaries and fruits gnawing out the pits of morbid shape in fruit flesh. Sometimes they reach a seed cavity or seeds.
